A number of disease conditions are associated with the action of bacteria in the oral cavity. For example, gingivitis, an inflammation or infection of the gums and alveolar bones, is generally believed to be caused by plaque causing bacterial and the toxins formed as by-products from the bacteria. In addition, plaque provides a locus for calculus or tartar formation. Periodontitis is generally believed to occur where unremoved plaque hardens into calculus (tartar), which affects the periodontal ligaments. As plaque and tartar continue to build up, the gums begin to recede, which can lead to continued inflammation, infection and potentially the loss of teeth.
To prevent or treat these diseased conditions, antibacterial agents may be incorporated into oral care compositions such as toothpaste and mouthwashes or rinses. Application of antibacterial compositions in the oral cavity tends to retard plaque formation and related oral infections. It is also common to provide oral compositions containing components that remove or prevent the build-up of tartar. Effective antitartar agents, such as phosphates, are believed to work in-part by interfering with crystalline growth of hydroxyapatite on the tooth surface.
The antiplaque efficacy of antibacterial compounds in a dentifrice composition depends on a number of factors, including the presence of other ingredients that may interfere with its action. For example, certain cationic antibacterial compounds and certain nonionic antibacterial compounds lose their effectiveness when formulated with certain anionic surfactants or other anionic active ingredients, such as tartar control phosphates. In many instances, it is preferred to use antibacterial compounds that do not show the adverse interactions with such anionic components.
Extracts from Magnolia officinalis (hereinafter “magnolia”), and especially from the bark, contain biphenol antibacterial compounds. The extracts have been found to have antibacterial effectiveness when formulated into, for example, toothpaste formulations.
Extracts prepared from natural sources such as magnolia are variable in composition and may contain many compounds other than the particular actives for which the extract is prepared. In addition, the composition of the extracts can vary from season to season and between different geographical regions. For these many reasons, it may be desirable to synthesize naturally occurring products such as those found in magnolia extracts.